Reddit user Clay, username PifflesTheGreat, posted the following photo of a window, which you might struggle to believe isn’t a painted picture.

Clay, a student, shot the bizarre trick of the eye through a normal, clear window at their friend’s house in southern California and they believe the illusion is a technological marvel.

“I believe it is because the view through the window does not appear overexposed while the walls on the inside do not appear underexposed,” Clay told the Press Association. “This is a result of the HDR (High-dynamic-range) used on my camera when taking the photos.

“Because the outside does not look blown out in comparison to the inside, it almost seems like the view is part of the interior.”

It is perhaps for this reason that the illusion even appears to work at different angles, though to a much lessened extent – the next picture being taken on an overcast day.

The window from a different angle

The post has been hugely popular on Reddit’s Mildly Interesting page, with almost 60,000 upvotes.

“As far as optical illusions go, I think people like them because it gives a little surprise that wasn’t expected,” said Clay.